Shear connector using perforated and/or cut out plate

ABSTRACT

The present invention relates to a shear connector having perforated and/or cut-out plates. In a T-shaped steel plate having a certain length, there are provided a plurality of through holes at a flange and a web. The flanges may be cut-out in biased method, and a plurality of through holes may be formed at the web. In the present invention, it is possible to achieve a perfect combination or a partial combination effect between a steel material and concrete. In addition, it is possible to enhance a weight resistance ability and a resistance ability with respect to transformation in such a manner that weight transfer function is provided between different materials.

TECHNICAL FIELD

The present invention relates to a shear connector used between a steelmaterial and a concrete, and in particular to a shear connector using aperforated and/or cut-out plate.

BACKGROUND ART

A combined structure used in architecture, or civil engineering field,etc. is designed with long span and high weight. Therefore, a desiredstrength is not achieved with only a pure steel structure, and a steelmaterial needed is increased. Therefore, a constructed cross section ora material strength gets increased using a large mass concrete forthereby enhancing a weight resistance ability.

In particular, when a bending member is implemented using a combinedstructure, a shear connector is installed between a steel beam and aconcrete slave for thereby achieving a mechanical adhering force(namely, shearing resistance) against a horizontal shear force.

FIG. 5 is a view illustrating a beam member capable of supporting abending moment in such a manner that a H steel beam member 51 and aconcrete slave 52 are formed integrally by a stud connector 53. The beamcan be classified into a combined beam and a non-combined beam dependingon the presence of a shear connector.

In the non-combined beam in which the shear connector is not installedbetween the concrete slave and steel material, there are atransformation state and a bending stress distribution with respect toan operation bending moment as shown in FIGS. 6 a through 6 c. At thistime, it is assumed that a friction force between the concrete slave andthe steel material surface is too weak, so that it can be neglected.

As shown therein, the concrete slave 52 and the steel beam 51 formneutral axes Z_(s) and Z_(b), respectively and are bendable. At thistime, a slip phenomenon may occur between the steel beam surface and theconcrete. In addition, an uplift force f_(up) occurs at a contactingsurface between the steel beam surface and the concrete.

FIGS. 7 a through 7 c are views illustrating a transformation state anda bending stress distribution with respect to an operation bendingmoment in a combined beam which the enough amount of shear connectorsare installed at an upper side of the beam so that a slip phenomenondoes not occur between the concrete slave and the steel beam.

The resistance at the cross section has an in-facial shear stress(horizontal shear force σ_(h)) and an out-facial shear force (verticalshear force σ_(v), uplift force). Namely, a shear connector having theabove two resistance functions should be provided in order to obtain aperfect combination between the concrete and the steel material.

Generally, a stud connector has been used as a shear connector in orderto achieve a combined effect between the steel material and the concretein architecture, or civil engineering field, etc., for therebytransferring an in-facial shear force between different materials.

In the stud connector, a circular head and a body are formed integrally.An arc stud welding machine is needed for a work at a construction site,or a factory, etc.

However, the arc stud welding needs 220V/380V (three-phase) voltage andover fixed rate current of 350˜1000KA. Therefore, there are manyproblems in that it is impossible to obtain a fixed rate voltage orcurrent at a remote area or a small size factory.

In addition, since the conventional stud connector has a small sizehead, a desired combination effect cannot be achieved in materialseparation prevention with respect to uplift force and an anchorageeffect.

Furthermore, the anchorage effect may be decreased due to a frequentvibration or fatigue weight load.

DISCLOSURE OF INVENTION

Accordingly, it is an object of the present invention to provide a shearconnector having a perforated and/or cut-out plate capable of overcomingthe problems encountered in the conventional art.

It is another object of the present invention to provide a shearconnector having a perforated and/or cut-out plate capable of beingeasily constructed, achieving a perfect combination and a partialcombination effect and enhancing a weight resistance ability and aresistance ability with respect to transformations in such a manner thata weight transfer function is provided between different materials.

It is further another object of the present invention to provide a shearconnector having a perforated and/or cut-out plate capable of achievingthe same resistance performances with respect to an in-facial shearstress and an out-facial shear stress.

To achieve the above objects, according to an aspect of the presentinvention, in a T-shaped steel plate having a predetermined length,there is provided a shear connector, comprising a flange and a webhaving a plurality of holes.

To achieve the above objects, according to other aspect of the presentinvention, in a T-shaped steel plate having a predetermined length,there is provided a shear connector, comprising a flange formed of aplurality of flange pieces cut-out in biased shapes, and a web having aplurality of holes.

To achieve the above objects, according to another aspect of the presentinvention, in a Z-shaped steel plate having a predetermined length,there is provided a shear connector, comprising an upper flange and aweb having a plurality of through holes.

Therefore, in the present invention, a combination operation with asteel material is enhanced, so that a separation is prevented betweenconcrete and a steel material, and thereby, a resistance with respect toa uplift operation and a facial shear resistance are enhanced.

BRIEF DESCRIPTION OF DRAWINGS

The present invention will become better understood with reference tothe accompanying drawings which are given only by way of illustrationand thus are not limitative of the present invention, wherein;

FIGS. 1 a and 1 b are perspective views of a shear connector accordingto a first embodiment of the present invention;

FIGS. 2 a and 2 b are perspective views of a shear connector accordingto a second embodiment of the present invention;

FIGS. 3 a and 3 b are perspective views of a shear connector accordingto a third embodiment of the present invention;

FIG. 4 is a perspective view of another example of a shear connectoraccording to a first embodiment of the present invention;

FIG. 5 is a partly cut-out perspective view of a beam member combinationbeam capable of resisting a bending moment in such a manner that aH-shaped beam member 51 and a concrete slave 52 are integrated using astud connector 53;

FIGS. 6 a through 6 c are views illustrating a transformation state anda bending stress distribution in a non-combined beam in which a shearconnector is not installed between a concrete slave and a steel beam;and

FIGS. 7 a through 7 c are views of a transformation state and a bendingstress distribution with respect to an operation bending moment in abeam combined with a concrete slave wherein the enough amount of shearconnectors are installed at an upper side of the steel beam so that aslip phenomenon does not occur between the concrete slave and the steelbeam.

BEST MODE FOR CARRYING OUT THE INVENTION

The preferred embodiments of the present invention will be describedwith reference to the accompanying drawings.

FIG. 1 a is a view of a shear connector 1 according to a firstembodiment of the present invention. As shown therein, the shearconnector 1 according to a first embodiment of the present invention isformed of a T-shaped steel having a flange 10 and a web 20. A pluralityof through holes 12 and 22 are formed at the flange 10 and the web 20 atregular intervals.

Here, the through holes 12 and 22 are provided in order to increase acombining operation with concrete. As shown in FIG. 1 a, there are shownthe shapes of the through holes 12 and 22. However, the shapes are notlimited to the shapes of FIG. 1 a. The through holes 12 and 22 may beformed in a rectangular shape, a triangle shape and a diamond shape. Inaddition, in the case that a corner is formed at the through hole like atriangle shape, a rectangular shape and a diamond shape, as shown inFIG. 1 b, a rounding portion 14 is formed in order to prevent a certainfatigue breakdown by a corner stress concentration.

The through holes 12 and 22 formed in the flange 10 and the web 20 aredesigned to secure a continuity of the concrete and are capable ofpreventing a material separation based on a wedge function with respectto the horizontal and the vertical shear forces. In addition, reinforcedsteel may be inserted into the through holes 12 and 22, respectively.Here, the reinforced steel is provided to enhance vertical andhorizontal shear stresses. Namely, a brittleness property of theconcrete is changed into a malleability property.

The flange 10 is provided in order to achieve a desired mounting effectwith respect to an uplift force by limiting a flange lower concrete forthereby preventing a separation between the contacting surfaces of thematerials.

FIGS. 2 a and 2 b are views illustrating a shear connector 2 accordingto second embodiment of the present invention. A plurality of throughholes 22 are formed on the web 20. The plate forming the flange 10 isformed of a plurality of flange pieces 16 and 18 wherein the flangepieces are cut-out in a biased shape.

At this time, the construction that the flanges 10 are cut-out based ona biased method is provided in order to prevent the problems that theconcrete is not effectively filled in the lower side of the flange afterthe concrete is filled. The brittleness breakage is prevented during theshearing resistance by slightly decreasing the strength of the flange.Therefore, the malleability property can be achieved.

In addition, the cut-out flanges 10 are capable of coping with thehorizontal shear stresses by the wedge functions of the concrete.

The through holes 22 formed at the web 20 can be formed in variousshapes like the first embodiment of the present invention. In the casethat a corner portion is formed at the through holes in a triangleshape, a rectangular shape, and a diamond shape, a fatigue breakage mayoccur by the corner stress concentration as shown in FIG. 2 b.Therefore, a rounding portion 14 is provided in order to decentralizethe stress concentration.

FIGS. 3 a and 3 b are views illustrating a shear connector 3 accordingto third embodiment of the present invention. As shown therein, in aZ-shaped steel plate, a plurality of through holes are formed at anupper flange and a web. At this time, a lower flange 30 is designed toenhance the weldability for thereby achieving a stable adherence withthe steel material.

In the preferred embodiments of the present invention, a plurality ofprotrusions (not shown) and/or grooves (not shown) can be formed at theweb and the flange for thereby enhancing a friction force with theconcrete.

As shown in FIG. 4, the web 20 of the shear connector 1, 2 or 3according to the present invention may be formed to have a plurality ofridges and valley portions in the shape of a wave. Therefore, it ispossible to guide a small size breakage, not a big size breakage basedon a pocket effect of concrete filled into the valley portions of theweb 20.

INDUSTRIAL APPLICABILITY

As described above, in the present invention, it is possible to achievea perfect combination and a partial combination effect between a steelmaterial and concrete. In addition, a weight resistance ability and aresistance ability with respect to transformation are significantlyenhanced in such a manner that a weight transfer function is providedbetween different materials.

The present invention is not limited to the above embodiments. As thepresent invention may be embodied in several forms without departingfrom the spirit or essential characteristics thereof, it should also beunderstood that the above-described examples are not limited by any ofthe details of the foregoing description, unless otherwise specified,but rather should be construed broadly within its spirit and scope asdefined in the appended claims, and therefore all changes andmodifications that fall within the meets and bounds of the claims, orequivalences of such meets and bounds are therefore intended to beembraced by the appended claims.

1. A shear connector having a predetermined length in a T-shaped steelplate, comprising: a flange and a web having a plurality of throughholes.
 2. The connector of claim 1, wherein said web has a plurality ofvalley portions and ridges in wave shapes.
 3. The connector of claim 1,wherein a plurality of protrusions and/or grooves are formed at theflange and the web.
 4. The connector of claim 3, wherein said web has aplurality of valley portions and ridges in wave shapes.
 5. A shearconnector having a predetermined length in a T-shaped steel plate,comprising: a flange formed of a plurality of flange pieces wherein saidflange pieces are cut-out in biased shapes; and a web having a pluralityof through holes.
 6. The connector of claim 5, wherein said web has aplurality of valley portions and ridges in wave shapes.
 7. The connectorof claim 5, wherein a plurality of protrusions and/or grooves are formedat the flange and the web, respectively.
 8. The connector of claim 7,wherein said web has a plurality of valley portions and ridges in waveshapes.
 9. A shear connector having a predetermined length in a Z-shapedsteel plate, comprising: an upper flange and a web having a plurality ofthrough holes.
 10. The connector of claim 9, wherein said web has aplurality of valley portions and ridges in wave shapes.
 11. Theconnector of claim 9, wherein a plurality of protrusions and/or groovesare formed at the flange and the web, respectively.
 12. The connector ofclaim 11, wherein said web has a plurality of valley portions and ridgesin wave shapes.